Heel-and-toe
Encyclopedia
- Not to be confused with left-foot brakingLeft-foot brakingLeft-foot braking is the technique of using the left foot to operate the brake pedal in an automobile, leaving the right foot dedicated to the throttle pedal...
Heel-and-toe is a driving technique used mostly in performance driving, although some drivers use it on the road in everyday conditions in the interest of effectiveness. It involves operating the throttle and brake pedals
Automobile pedal
An automobile may have two to four foot pedals. The arrangement is the same for both right- and left-hand traffic. From left to right:* normally operated by the left foot:**clutch pedal, not in the case of automatic transmission...
simultaneously with the right foot, while facilitating normal activation of the clutch
Clutch
A clutch is a mechanical device which provides for the transmission of power from one component to another...
with the left foot. It is used when braking and downshifting simultaneously (prior to entering a turn), and allows the driver to "blip" the throttle to raise the engine speed and smoothly engage the lower gear
Gear
A gear is a rotating machine part having cut teeth, or cogs, which mesh with another toothed part in order to transmit torque. Two or more gears working in tandem are called a transmission and can produce a mechanical advantage through a gear ratio and thus may be considered a simple machine....
. (See Synchronized transmission.)
Usage
Heel-toe or heel-and-toe double-declutching is used before entry into a turn while a vehicle is under braking, preparing the transmissionTransmission (mechanics)
A machine consists of a power source and a power transmission system, which provides controlled application of the power. Merriam-Webster defines transmission as: an assembly of parts including the speed-changing gears and the propeller shaft by which the power is transmitted from an engine to a...
to be in the optimal range of rpm to accelerate out of the turn. One benefit of downshifting before entering a turn is to eliminate the jolt to the drivetrain, or any other unwanted dynamics. The jolt will not upset the vehicle as badly when going in a straight line, but the same jolt while turning may upset the vehicle enough to cause loss of control if it occurs after the turn has begun. Another benefit is that "heel-and-toeing" allows the driver to downshift at the last moment before entering the turn, after starting braking and the car has slowed, so the engine speed will not be too high when the lower gear is engaged.
Performance vehicles are usually modified (if necessary) so that the heights of the brake and accelerator pedals are closely matched and the pedals are not too far apart, to permit easy use of heel-and-toe.
The name, stemming from earlier automotive designs where the accelerator pedal was on the left and could be actuated with the heel while the brake pedal was actuated with the toe, is misleading regarding how the technique is carried out in modern cars, i.e., operating the brake with the left edge of the foot, while rocking it down and to the right to operate the throttle. With practice, it becomes possible to smoothly and independently operate both pedals with one foot. The technique is common in all forms of motorsport, especially rallying
Rallying
Rallying, also known as rally racing, is a form of auto racing that takes place on public or private roads with modified production or specially built road-legal cars...
.
As the power band of most rally cars is high in the rev range, this technique can also be used to ensure that engine rpm does not drop below the power band of the car while under braking. If this happened there would be a delay between the driver accelerating after the corner and when the car responds; this is especially true in turbocharged cars. This technique ensures that maximum power can be reached the instant the brake pedal is released and the accelerator fully depressed.
Note
An unrelated technique called left-foot brakingLeft-foot braking
Left-foot braking is the technique of using the left foot to operate the brake pedal in an automobile, leaving the right foot dedicated to the throttle pedal...
should not be confused with heel-and-toe.